土壤盐碱改良剂施用量及施用时期研究

土壤盐碱改良剂在一定程度上能够起到松土、保湿、改良土壤理化性状的作用,促进植物对养分和水分的吸收,比传统的工程水利和生物改良方法简便易行、成本低、效果好,可较好的解决滨海盐渍土盐、板、瘦的问题,是一项改良治理滨海盐渍土的新措施.通过此技术的推广实施,可提高作物产量,扩大可利用农业土地资源,改善当地生态环境,推动经济发展,促进黄河三角洲的可持续发展.     

区域滩涂资源开发管理系统的设计与实现

利用地理信息系统(GIS)作为核心软件开发的江苏盐城滩涂资源开发管理系统,成功地对该区域的滩涂资源进行了动态监测,在过去7年中围垦滩涂的速度年均上升了1 417/hm2,运行及测试结果表明,该系统达到了预定的技术要求.     

Processing of Yield Map Data

Yield maps reflect systematic and random sources of yield variation as well as numerous errors caused by the harvest and mapping procedures used. A general framework for processing of multi-year yield map data was developed. Steps included (1) raw data screening, (2) standardization, (3) interpolation, (4) classification of multi-year yield maps, (5) post-classification spatial filtering to create spatially contiguous yield classes, and (6) statistical evaluation of classification results. The techniques developed allow more objective mapping of yield zones, which are an important data layer in algorithms for prescribing variable rates of production inputs.     

绿色食品生产分区布局的研究--以辽宁省铁岭市为例

结合铁岭市生态环境质量和农业发展现状,采用聚类分析和灰色诊断的方法,对铁岭市绿色食品生产进行了分区布局,以便为绿色食品生产的产业化和区域化提供参考。铁岭市绿色食品生产可分为4个区:Ⅰ区包括开原市、铁岭县和清河区,该区拟发展为铁岭市农、林、牧、副为一体,产、加、销相结合的绿色食品综合开发区。Ⅱ区是昌图县,定为铁岭市绿色种植业和绿色畜牧业的生产区。Ⅲ区是西丰县,该区应作为铁岭市绿色林产品和特产生产区,走以林为主,农、林、牧、副相结合的绿色食品发展道路。Ⅳ区是调兵山市,该区适宜发展城郊型绿色农业和绿色食品加工业。     

Management Zones Classified With Respect to Drought and Waterlogging

Within-field variations in potential grain yield may be due to variations in plant available soil water. Different water holding capacities affect yield differently in different years depending on weather. By estimating plant-water availability in different weathers, scenarios could be created of how yield potential and thereby fertilizer demand may vary within fields. To test this, measured cereal grain yields from a dry, a wet and an intermediate year were compared with different soil moisture related variables in a Swedish arable field consisting of clayey and sandy areas. Soil water budget calculations based on weather data and maximum plant available water (PAW), estimated from soil type and rooting data, were used to assess drought. A reasonable correlation between estimated and measured soil moisture was achieved. In the dry year, drought days explained differences in yield between the clayey and the sandy soil, but yield was better explained directly by maximum PAW, elevation, clay content and soil electrical conductivity (SEC). Yield correlated significantly with SEC and elevation within the sandy soil in the dry year and within the clayey soil in the wet year, probably due to water and nitrogen limitation respectively. Dense SEC, elevation and yield data were therefore used to divide the field into management zones representing different risk levels for drought and waterlogging. These could be used as a decision support tool for site-specific N fertilization, since both drought and waterlogging affect N fertilization demand.     

Is it economically feasible to harvest by management zone?

The economics of harvesting wheat based on input management zones in the northern wheatbelt of Western Australia was studied using a simulated field of regular dimensions with varying zone sizes and layouts. Fertilizer application rates and crop yield and quality data from field trials of input management were used to estimate the gross crop revenue and harvesting costs from the different field layouts and zone combinations. As a general observation there was no consistency in the results; harvesting by zone generated more gross income in some combinations of field layout and yield quantity scenarios, but not in others. However, there were key factors in determining whether it was profitable to harvest by zone. These were prior knowledge of the potential yield and quality characteristics of grain from each zone in a field, and the layout of zones within a field.     

园林专业学生学习计算机辅助设计软件的误区与解决方法

计算机软件制图以其方便、快捷、效果好等优点被广泛应用于设计行业,计算机辅助设计软件课程在园林专业中已开设多年,学生在学习过程中出现了一些误区,对解决方法进行初步探讨。     

浅述木麻黄沿海防护林造林技术

利用木麻黄营造沿海沙地防护林,不仅符合适地适树的造林原则,而且也是保护和恢复全省海防林带生态工程的有效途径之一.因此持续性发展木麻黄沿海防护林、苗木品种和造林技术至关重要.文章介绍了木麻黄沿海防护林造林技术,并对以后的造林工作提出了一些建议.     

冀东滨海重盐碱地原土绿化技术

针对冀东滨海重盐碱地原土绿化存在的问题,从整地、土壤改良、树种配置、育苗、栽植与管护等方面阐述了滨海重盐碱地原土绿化技术。